Thread cutter and ripping device



Dec. 31, 1935. T. D. LEWIS THREAD CUTTER AND RIPPING DEVICE Filed Aug. 15, 1954 INVENTOR I w 6 fl 3 T m m f 7 6 h a m gives T f amvil7 6 m I l E 8 m 0 WHJUVHJIIVS/ I I Z 4 6.

ATTO RNEY,

Patented Dec. 31, "1935 UNITED STATES PATENT OFFICE THREAD CUTTER AND RIPPING DEVICE Theodore D. Lewis, Kansas City, Mo. Application August 15, 1934, Serial No. 739,950

1 Claim. (01. 164-175) My invention relates to thread cutting and ripping devices, and my object is to provide a simple, inexpensive and efiicient device of this character which may be attached to a sewing '5. machine in lieu of the customary needle, for the purpose of cutting threads and ripping seams.

By providing a device of this character the operation of ripping seams may be performed in much less time than is required for performing the same work manually with a pair of scissors or other cutting device. The use of the device also leaves both hands of the operator free to guide the seam so that the ripping of the threads thereof may be accurately accomplished without danger of cutting the goods.

In order that the invention may be fully understood, reference will now be had to the accompanying drawing, in which:

Fig. 1 shows a portion of a sewing machine with my thread cutting and ripping device attached thereto.

Fig. 2 is an enlarged detail perspective view of the device.

Fig. 3 is an enlarged front elevation of the device.

Fig. 4 is an enlarged cross sectional view on line 4-4 of Fig. 3.

Referring in detail to the different parts, A designates the head of a sewing machine which may be either of the manually operated type or the electric motor driven type. B is the customary needle holder on the lower end of the reciprocatory needle bar b of the sewing machine. The needle holder B is equipped with the usual set screw C for firmly holding either the ordinary sewing machine needle or my device in position for use.

Referring now more particularly to the present invention, 2 designates my device which comprises a body portion having a fiat side 8 extending the full length thereof as shown by Fig. 3. The lower end of the body portion terminates in a point 1 from which a cutting edge 4 9 extends upwardly and outwardly to the opposite sideof said body portion at an angle of approximately degrees, from a horizontal plane, Fig. 3. The upper part of the body portion comprises an enlarged shank 4 of semicircular cross sectional configuration and the lower part 6 of the body portion is greatly reduced in thickness and is of triangular cross 5 sectional configuration as shown by Fig. 4 to provide a cutting edge I 0 which extends upwardly a suitable distance from one end of the cutting edge 9.

In practice the upperend of the shank 4 is- 10 placed in the holder B with the flat side 8 adjacent to the set screw C, so that when the latter is tightened the device will be securely held from turning in said. holder B. The flat side 8 also acts as a guide in properly positioning 15 the cutting edges 9 and ll) of the device preparatory to performing the work of cutting threads or ripping seams.

When. in operation it is apparent that the device will travel up and down at high speed and 20 thus cut threads or rip seams as rapidly as they can be fed to said device.

From the foregoing description, taken in connection with the drawing, it is apparent that I have provided a device which is well adapted 26 for the purpose intended, and while I have shown a preferred embodiment of the invention I reserve all rights to such changes and modifications thereof as properly fall within the spirit and scope of the invention as claimed. 30

Having thus described my invention, what I claim and desire to secure by Letters Patent, is:

A thread cutter and ripping device comprising a body portion having a fiat side extending the full length of the device and terminating at its lower end in a point, a cutting edge extending upwardly and outwardly from said point to the opposite side of the body portion at an angle of approximately 75 degrees, the upper part of the body portion comprising an enlarged shank of 40 semicircular cross sectional configuration and the lower part of the'body portion being greatly reduced in thickness and of triangular cross sectional configuration to provide a cutting edge extending upwardly a suitable distance from one 45 end of the first-mentioned cutting edge.

THEODORE D. LEWIS. 

